Are the bloooms toxic in any way?
I have not been able to confirm the toxicity of the Pink Trumpet Tree.
I would not consume any parts of this tree to be safe.
What should I use?
My research shows that pests and diseases are not a serious concern with trumpet tree. However, verticillium wilt is a soil borne disease that can cause yellowing and leaf curling. Anthracnose is a fungal disease that can cause brown spots and leaf curl. I would suggest calling your local university extension service to determine an accurate diagnosis to get the correct treatment.
I heard that trumpet trees are poisonous. I have two trees doing very well in my garden but I usually plant some vegetables in the same place in the fall. I live in Tampa Florida.
I really wouldn't plant vegetables within the drip line of any tree because you may disturb their roots, plus you may be shading your vegetables.